AT LEAST one of the major fires threatening communities in Sydney's far west this week was sparked by an arson attack, police have confirmed.
They said the Marsden Park blaze was deliberately lit on Monday and flared up to threaten homes on Tuesday.
Another fire at Winmalee, in the Blue Mountains, was fuelled by strong winds where hazard reduction burning was being carried out by NSW Parks and Wildlife staff.
At Windsor, fallen power lines were to blame for a blaze which burned through more than 1000ha of land.
The cause of a fire at Londonderry is yet to be determined.
More than 60 fires continued to burn across NSW.
All were contained.
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